Heart of the Swarm and Legacy of the Void are considered to be expansion sets[18] and will be priced as such. Each will upgrade and expand multiplayer content in addition to containing a campaign, such as the possibility of new units, abilities and structures.New units available in the expansions can only be accessed if a player buys the expansion. Each product would have upgrades to the multiplayer, "that's the whole point of the expansion or the second part". Each race will be enhanced in some way.